Method and system for fabricating semiconductor components with through interconnects and back side redistribution conductors

ABSTRACT

A method for fabricating semiconductor components includes the step of providing a semiconductor substrate having a circuit side, a back side, a plurality of integrated circuits on the circuit side, and a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits. The method also includes the steps of forming vias from the back side to the substrate contacts, forming a conductive layer in the vias and on the back side in electrical contact with the substrate contacts; and forming the conductive layer on the back side into a plurality of conductors in electrical communication with the substrate contacts. The semiconductor component includes the semiconductor substrate, the through interconnects and the redistribution conductors. Each through interconnect includes a via aligned with a substrate contact, and a conductive layer at least partially lining the via in physical and electrical contact with the substrate contact. Each conductor is formed by a portion of the conductive layer.

BACKGROUND

In fabricating semiconductor components, it is sometimes necessary toprovide interconnects that transmit signals from the circuit side of asemiconductor substrate to the back side of the semiconductor substrate.Interconnects which extend through the semiconductor substrate from thecircuit side to the back side are sometimes referred to as “throughinterconnects”. During fabrication of semiconductor substrates at thewafer level through interconnects are sometimes referred to as “throughwafer interconnects” (TWI).

Typically through interconnects comprise metal filled vias formed in thesemiconductor substrate, that are configured to electrically connect theintegrated circuits on the circuit side to electrical elements on theback side of the semiconductor substrate. For example, the back side ofthe semiconductor substrate can include redistribution conductors andterminal contacts in electrical communication with the throughinterconnects. The metal in through interconnects typically comprises ahighly conductive metal, such as copper or solder, formed as a plug thatcompletely fills a via. In addition, a deposition process, such asscreen printing, deposition through a nozzle, or capillary injection canbe used to deposit the metal into the via to form the plug.

As semiconductor components become smaller and have higher input/outputconfigurations, semiconductor manufacturers must fabricate throughinterconnects with increasingly smaller sizes and pitches, but withoutcompromising performance. With regard to performance, throughinterconnects having a high electrical conductivity and a low parasiticcapacitance provide the best performance. Conventional metal filledthrough interconnects do not have optimal performance characteristics,particularly at elevated temperatures.

In addition to having good performance characteristics, it isadvantageous for through interconnects to be capable of fabrication atthe wafer level using equipment and techniques that are known in theart. It is also advantageous to incorporate as few steps as possible inthe fabrication process in order to minimize cost and defects.Conventional metal filled through interconnects require at least twophotopatterning steps, and both front side (circuit side) and back sideprocessing. For example, back side conductors and pads for terminalcontacts, which are in electrical communication with the metal filledthrough interconnects, are made separately, and require additional photopatterning and fabrication steps. The requirement of multiple photopatterning and fabrication steps, and both front side and back sideprocessing, can be very costly.

Another consideration in the fabrication of semiconductor componentswith through interconnects is the fragility of the integrated circuitscontained on the semiconductor substrates. During wafer processing theseintegrated circuits, as well as other elements contained on thesemiconductor substrates, must be protected from damage. Radiationsensitive integrated circuits contained on imaging semiconductorsubstrates, such as image sensor dice, are particularly vulnerable todamage during fabrication of through interconnects and back sideconductors. Further, the semiconductor industry is moving towards chipscale packages that utilize thinned semiconductor substrates. It wouldbe advantageous for a fabrication method for semiconductor componentswith through interconnects to be capable of handling thinnedsemiconductor substrates.

The method to be hereinafter described is directed to a wafer levelfabrication method for semiconductor components with throughinterconnects, which addresses the above noted considerations. Inaddition, improved semiconductor components with through interconnects,and improved systems containing the semiconductor components will behereinafter described.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments are illustrated in the referenced figures of thedrawings. It is intended that the embodiments and the figures disclosedherein are to be considered illustrative rather than limiting.

FIGS. 1A-1I are enlarged schematic cross sectional views illustratingsteps in a method for fabricating a semiconductor component with throughinterconnects and back side redistribution conductors;

FIG. 2A is an enlarged schematic bottom view taken along line 2A-2A ofFIG. 1A;

FIG. 2B is an enlarged schematic plan view taken along line 2B-2B ofFIG. 1C:

FIG. 2C is an enlarged schematic plan view taken along line 2C-2C ofFIG. 1G;

FIG. 3A is an enlarged schematic plan view, partially cut away, of thesemiconductor component;

FIG. 3B is an enlarged schematic cross sectional view of thesemiconductor component taken along section line 3B-3B of FIG. 3A;

FIG. 3C is an enlarged schematic bottom view, partially cut away, of thesemiconductor component taken along line 3C-3C of FIG. 3B; and

FIG. 4 is a schematic diagram of a system incorporating thesemiconductor component.

DETAILED DESCRIPTION

As used herein, “semiconductor component” means an electronic elementthat includes a semiconductor substrate or makes contact with asemiconductor substrate. “Semiconductor substrate” means an electronicelement, such as a semiconductor die, or a semiconductor package thatincludes integrated circuits and semiconductor devices. A “semiconductorwafer” means a substrate or portion thereof containing a plurality ofsemiconductor substrates or packages. “Wafer-level” means a processconducted on an element, such as a semiconductor wafer, containingmultiple semiconductor components or substrates. “Die level” means aprocess conducted on a singulated element, such as a singulatedsemiconductor die or package. “Chip scale” means having an outline aboutthe same as that of a semiconductor substrate. “Wafer size” means havingan outline about the same as that of a semiconductor wafer.“Interconnect” means an electrical element which electrically connectselectrical elements and transmits signals between these elements.“Through interconnect” means an electrical element which electricallyconnects electrical elements on different planes or surfaces of asemiconductor substrate and transmits signals between these elements.

Referring to FIGS. 1A-1I, 2A-2C and 3A-3C, a method for fabricatingsemiconductor components 10 (FIG. 3A) with through interconnects 11(FIG. 3B) and back side redistribution conductors 12 (FIG. 3C) isillustrated. Initially, as shown in FIG. 1A, a semiconductor substrate14 can be provided. By way of example, the semiconductor substrate 14(FIG. 1A) can comprise an image sensor die (or an image sensor package)having an imager pixel array 16 (FIG. 1A), and a plurality of integratedcircuits 18 (FIG. 1A) in the imager pixel array 16 (FIG. 1A), and onother portions of the semiconductor substrate 14 (FIG. 1A) as well. Theintegrated circuits 18 (FIG. 1A) can include radiation sensitiveintegrated circuits in the pixel array 16 (FIG. 1A), such ascomplimentary metal oxide semiconductor (CMOS) devices. The integratedcircuits 18 (FIG. 1A) can also include other types of integratedcircuits outside of the imager pixel array 16 (FIG. 1A) for processingimage data.

Rather than being an image sensor die (or image sensor package), thesemiconductor substrate 14 (FIG. 1A) can comprise another type ofsemiconductor die, or semiconductor package, having integrated circuitsconstructed in a desired electrical configuration using activesemiconductor devices. For example, the semiconductor substrate 14 (FIG.1A) can comprise a high speed digital logic device, such as a dynamicrandom access memory (DRAM), a static random access memory (SRAM), aflash memory, a microprocessor, a digital signal processor (DSP), anapplication specific integrated circuit (ASIC), a MEMS type device(e.g., accelerometer, microphone, speaker, electro mechanical device),or a solar cell. In addition, the semiconductor substrate 14 cancomprise a tested die that has been certified as a known good die (KGD).

As shown in FIG. 2A, the semiconductor substrate 14 is initiallycontained on a semiconductor wafer 20, which includes a plurality ofsubstantially identical semiconductor substrates 14. However, although asemiconductor wafer 20 is illustrated, it is to be understood that themethod can be performed on any substrate which contains one or moresemiconductor substrates 14. For example, rather than the semiconductorwafer 20 (FIG. 2A), a substrate can comprise a portion of asemiconductor wafer, a panel, a leadframe or a circuit board containingmultiple semiconductor substrates. In the claims to follow, the term“substrate” is used to encompass all of these elements. Thesemiconductor substrate 14 (FIG. 2A), and the semiconductor wafer 20(FIG. 2A) as well, can have any desired thickness. As such, thesemiconductor wafer 20 (FIG. 2A) can comprise a “full thickness” wafer,or a “thinned” wafer.

As shown in FIG. 1A, the semiconductor substrate 14, and thesemiconductor wafer 20 as well, include a circuit side 22 (front side),wherein the imager pixel array 16 and the integrated circuits 18 arelocated, and a back side 24. The circuit side 22 and the back side 24 ofthe semiconductor substrate 14 are major planar surfaces, which aregenerally parallel to one another, and separated by a thickness of thesemiconductor substrate 14. As shown in FIG. 2A, each semiconductorsubstrate 14 has a generally square, die sized, peripheral outline.However, the semiconductor substrates 14 can have any polygonalperipheral outline used in the art. For illustrative purposes in FIGS.1A-1I, a partial semiconductor substrate 14 is shown. In addition, thestreets or scribe area 36 (FIG. 2A) between adjacent semiconductorsubstrates 14 are denoted by spaces on the wafer 20 in FIG. 2A, and by avertical line in FIG. 1A.

As also shown in FIG. 1A, the semiconductor substrate 14 includes aplurality of substrate contacts 26 on the circuit side 22 in electricalcommunication with the integrated circuits 18 on the semiconductorsubstrate 14. The substrate contacts 26 can comprise device bond pads,or alternately redistribution contacts (i.e., contacts formed inconjunction with a redistribution layer (RDL)). In addition, thesubstrate contacts 26 can comprise a highly-conductive, bondable metal,such as aluminum or copper. The substrate contacts 26 can also comprisestacks of different metals, such as aluminum-nickel-gold,aluminum-nickel-solder, copper-palladium, and aluminum-copper.

For simplicity, each semiconductor substrate 14 (FIG. 2A) is illustratedwith only eight substrate contacts 26 (FIGS. 1A and 2A) arranged in anedge array along the peripheral edges of the semiconductor substrates14. However, in actual practice the semiconductor substrates 14 (FIGS.1A and 2A) can include tens to hundreds of substrate contacts 26 (FIGS.1A and 2A) arranged in a desired configuration, such as a center array,an edge array or an area array. Also in the illustrative embodiment, thesubstrate contacts 26 (FIGS. 1A and 2A) have a generally squareperipheral outline. However, as with the semiconductor substrates 14(FIG. 2A), the substrate contacts 26 (FIGS. 1A and 2A) can have anypolygonal shape including square, rectangular, circular, triangular andoval. In addition, a size of the substrate contacts 26 (FIGS. 1A and 2A)can be selected as required. For example, each substrate contact 26(FIGS. 1A and 2A) can have a width on each side of from about 5 μm to200 μm. Further, each substrate contact 26 (FIGS. 1A and 2A) cancomprise a generally planar pad as shown, or can have other shapes suchas a projection, a bump or a volcano shape.

As also shown in FIG. 1A, the semiconductor substrate 14 includes anelectrical insulation layer 30 formed on the circuit side 22 thereof.The electrical insulation layer 30 is configured to electricallyinsulate the integrated circuits 18, other integrated circuits outsideof the pixel array 16, and other electrical elements as well, from theremainder of the semiconductor substrate 14. The electrical insulationlayer 30 can comprise a die passivation layer, or a redistributioninsulation layer, formed of a material such as BPSG, SiO₂, or polyimide.For illustrative purposes, the substrate contacts 26 are illustrated asbeing on the electrical insulation layer 30. However, internalconductors (not shown) provide electrical paths between the substratecontacts 26 and the integrated circuits 18, between the substratecontacts 26 and other integrated circuits outside of the pixel array 16,and between the substrate contacts 26 and other electrical elements aswell. All of the elements of the semiconductor substrate 14 (FIG. 1A)including the integrated circuits 18 (FIG. 1A), the pixel array 16 (FIG.1A), the substrate contacts 26, and the insulation layer 30 (FIG. 1A),can be formed using well known semiconductor fabrication processes.

Next, as shown in FIG. 1B, spacers 32 and a wafer scale carrier 28 canbe attached to the circuit side 22 of the semiconductor wafer 20. Forsome applications, such as processing of a full thickness wafer, thecarrier 28 can be eliminated from the method. The spacers 32 (FIG. 1B)can have a selected size and geometry, and can comprise an electricallyinsulating material, such as a polymer material, a glass material or aceramic material attached to the substrate contacts 26 (FIG. 1B).Alternately, the spacers 32 (FIG. 1B) can be eliminated, and adhesivelayers (not shown) can be utilized to attach the carrier 28 (FIG. 1B) tothe wafer 20 (FIG. 1B). The carrier 28 (FIG. 1B) can comprise a glass orsilicon material having a selected thickness, and a selected peripheraloutline. In addition, the carrier 28 (FIG. 1B) can comprise a separatemember configured for attachment to the wafer 20 (FIG. 1B) to supportand protect the wafer 20 (FIG. 1B) and the integrated circuits 18 (FIG.1B) during processing. Because the steps of the method are performedprimarily from the back side 24 (FIG. 1B) of the wafer 20 (FIG. 1B), thecircuit side 22 (FIG. 1B) can remain face down and protected by thecarrier 28 (FIG. 1B). Still further, following further processing to behereinafter described, the carrier 28 (FIG. 1B) can be configured toprovide die sized transparent covers 28S (FIG. 3B) in the completedsemiconductor components 10 (FIG. 3B). In addition, the transparentcovers 28S (FIG. 3B) can be further processed as lenses, or separatelens structures can be attached to the covers 28S (FIG. 3B).

Rather than being configured to form transparent covers 28S (FIG. 3B),the carrier 28 (FIG. 1B) can comprise a temporary carrier that isremoved following the fabrication process. In this case, separatetransparent covers or lenses can be attached to the component 10 (FIG.3B) at the end of the fabrication method. For example, temporarycarriers made of glass, or temporary carrier in the form of blanksilicon wafers, can be fused by heat and adhesives to the wafer 20 (FIG.1B) to protect the circuit sides 22 of the semiconductor substrates 14during back side processes, such as etching, grinding and chemicalmechanical planarization (CMP). Suitable temporary carriers aremanufactured by 3-M Corporation of St. Paul, Minn., and others as well.Silicon wafers, which can also be utilized to form a temporary carrier,are also available from a variety of manufacturers.

As also shown in FIG. 1B, the back side 24 of the semiconductor wafer 20can be thinned to form thinned semiconductor substrates 14T. Thethinning step can be performed by mechanically planarizing the wafer 20(FIG. 1B), or by etching the wafer 20 (FIG. 1B). For example, thethinning step can be performed using a mechanical planarizationapparatus (e.g., a grinder). One suitable mechanical planarizationapparatus is manufactured by Okamoto, and is designated a model no.VG502. The thinning step can also be performed using a chemicalmechanical planarization (CMP) apparatus. A suitable CMP apparatus iscommercially available from a manufacturer such as Westech, SEZ, PlasmaPolishing Systems, or TRUSI. The thinning step can also be performedusing an etch back process, such as a wet etch process, a dry etchprocess or a plasma etching process. The thinned semiconductorsubstrates 14T (FIG. 1B) can have a selected thickness T (FIG. 1B) offrom about 10 μm to 700 μm.

Next, as shown in FIG. 1C, a back side insulation layer 34 can be formedon the semiconductor wafer 20, and on the back sides 24 of the thinnedsemiconductor substrates 14T. The back side insulation layer 34 (FIG.1C) can comprise a low dielectric constant (low k) polymer such aspolyimide, polybenzoxazole (PBO), or benzocyclobutene (BCB). The backside insulation layer 34 (FIG. 1C) can also comprise a low temperatureoxide or nitride layer. As also shown in FIG. 1C, the back sideinsulation layer 34 (FIG. 1C) can be patterned with openings 38 (FIG.1C) that align with the substrate contacts 26 (FIG. 1C) on the circuitsides 22 (FIG. 1C) of the thinned semiconductor substrates 14T (FIG.1C). By way of example, the back side insulation layer 34 (FIG. 1C) canbe initially blanket deposited to a desired thickness using a suitabledeposition process such as spin on, positive displacement through anozzle, screen printing or stenciling. The back side insulation layer 34(FIG. 1C) can then be patterned and cured using a suitable process, suchas wet chemical etching through a photo mask. Alternately, the back sideinsulation layer 34 (FIG. 1C) can comprise a photoimageable material,such as a resist or a photoimageable polyimide, that can be patterneddirectly without a photo mask. A size (e.g., diameter) of the openings38 (FIG. 1C) can be selected as required. For example, the openings 38(FIG. 1C) can be slightly smaller than the size of the substratecontacts 26 (FIG. 1C). A shape of the openings 38 (FIG. 1C) can also beselected as required. As shown in FIG. 2B, the openings 38 can have acircular shape, or alternately any polygonal shape. Patterning of theback side insulation layer 34 (FIG. 1C) to form the openings 38 (FIG.1C) is termed herein as photo alignment step 1.

Next, as shown in FIG. 1D, a via forming step can be performed in whichvias 44 (FIG. 1D) are formed from the back sides 24 of the thinnedsemiconductor substrates 14T (FIG. 1D) in alignment with the substratecontacts 26. Following the via forming step illustrated in FIG. 1D, thevias 44 are generally perpendicular (orthogonal) to the back sides 24 ofthe thinned semiconductor substrates 14T (FIG. 1D). The vias 44 (FIG.1D) can be formed using a dry or wet etch process that is endpointed atthe insulation layer 30 (FIG. 1D). For example, the vias 44 (FIG. 1D)can be formed using a dry etch process, such as a BOSCH etch.Alternately, the vias 44 (FIG. 1D) can be formed using a wet etchant anda wet etching process. For example, an anisotropic wet etch process canbe performed using a solution of KOH and H₂O, and an isotropic etchprocess can be performed using a solution of HF, HNO₃ and H₂O. The sizeof the vias 44 (FIG. 1D) can correspond to the size of the substratecontacts 26 (FIG. 1D). In FIG. 1D, the vias 44 are illustrated as beingslightly smaller than the substrate contacts 26. By way of example, thediameter of each via 44 (FIG. 1D) can be from 10 μm to 2 mils orgreater.

Preferably, the vias 44 (FIG. 1D) are formed by etching directly throughthe openings 38 (FIG. 1D) in the insulation layer 34 (FIG. 1D). With theinsulation layer 34 (FIG. 1D) used as an etch mask, a photo alignmentstep is not required for forming the vias 44 (FIG. 1D). In this case,the insulation layer 34 (FIG. 1D) can be made thick enough toaccommodate material loss during etching, or can comprise an etchresistant material.

As also shown in FIG. 1D, as an alternative to etching through theopenings 38 (FIG. 1D) in the insulation layer 34 (FIG. 1D), the vias 44(FIG. 1D) can be etched using an etch mask 40 (FIG. 1D). For example,the etch mask 40 (FIG. 1D) can formed on the insulation layer 34 (FIG.1D), and patterned with openings 42 (FIG. 1D) that align with theopenings 38 (FIG. 1D) in the insulation layer 34 (FIG. 1D). In thiscase, the etch mask 40 (FIG. 1D) can comprise a resist that is photopatterned with the openings 38 (FIG. 1D). Patterning of the etch mask 40(FIG. 1D) requires a photo alignment step which is termed herein asphoto alignment step 2.

Next, as shown in FIG. 1E, the insulation layer 30 (FIG. 1E) in the vias44 (FIG. 1E) can be removed to expose the inner surfaces 46 (FIG. 1E) ofthe substrate contacts 26 (FIG. 1E). The insulation layer 30 (FIG. 1E)in the vias 44 (FIG. 1E) can be removed using an etching process such asoxide dry etching.

Next, as shown in FIG. 1F, the vias 44 (FIG. 1F) are lined with viainsulation layers 48 (FIG. 1F) that will electrically insulate thethrough interconnects 11 (FIG. 3B) from the remainder of the thinnedsemiconductor substrates 14T (FIG. 1F). The via insulation layers 48(FIG. 1F) preferably have a thickness of only a few microns or less,such that the vias 44 (FIG. 1F) remain open. The via insulation layers48 (FIG. 1F) can comprise an electrically insulating polymer material,such as polyimide, that can be deposited into the vias 44 using asuitable process such as screen printing, deposition through a nozzle,or capillary injection. The via insulation layers 48 (FIG. 1F) can alsocomprise a polymer such as parylene, that can be vapor deposited intothe vias 44 (FIG. 1F), or an oxide, such as SiO₂ that can be eithergrown in place, or deposited using a suitable deposition process.Following the deposition process, excess insulating material can beremoved using a spacer etch, such that the vias 44 are lined, and theinner surfaces 46 (FIG. 1F) of the substrate contacts 26 (FIG. 1F) areexposed.

Next, as shown in FIG. 1G, a conductive layer 50 (FIG. 1G) is formed inthe vias 44 (FIG. 1G) in physical and electrical contact with thesubstrate contacts 26 (FIG. 1G), and on the back side 24 of the thinnedsemiconductor substrate 14T. The conductive layer 50 (FIG. 1G) forms thethrough interconnects 11 (FIG. 1I), the redistribution conductors 12(FIG. 2C), and the terminal contact pads 52 (FIG. 2C) for the terminalcontacts 56 (FIG. 1I). As such, the through interconnects 11 (FIG. 1I),the redistribution conductors 12 (FIG. 2C) and the terminal contact pads52 (FIG. 2C) comprise a same metal layer (i.e., the conductive layer 50)are formed using a same metal deposition step. For forming the throughinterconnects 11 (FIG. 1I), the conductive layer 50 (FIG. 1G) at leastpartially lines the sidewalls of the vias 44 (FIG. 1G), and at leastpartially lines the inner surfaces 46 (FIG. 1F) of the substratecontacts 26 (FIG. 1G). As with the via insulation layers 48 (FIG. 1G),the conductive layer 50 (FIG. 1G) is formed such that the vias 44 (FIG.1G) remain open. As such, the conductive layer 50 (FIG. 1G) can have athickness of only a few microns or less. In addition, as shown in FIG.2C, the conductive layer 50 (FIG. 2C) is patterned to cover selectedareas on the surface of the insulation layer 34 (FIG. 1G) circumjacentto the vias 44 (FIG. 2C).

One method for forming the conductive layer 50 (FIG. 1G) compriseselectroless deposition. One advantage of electroless deposition is thatthe redistribution conductors 12 (FIG. 2C), and the terminal contactpads 52 (FIG. 2C) as well, can be formed at the same time out of thesame metal layer. This eliminates at least one photo alignment steprelative to prior art methods for forming metal through interconnects,wherein separate photo patterning steps are used to form the throughinterconnects and the redistribution conductors. Another advantage ofthe outlined method is that the process steps can be performed from theback side 24 (FIG. 2B) of the wafer 20 (FIG. 2B) with the circuit side22 (FIG. 2A) of the wafer 20 protected by the carrier 28 (FIG. 1B).

As shown in FIG. 1G, for forming the conductive layer 50 (FIG. 1G), byelectroless deposition, a deposition mask 54 (FIG. 1G) can be formed onthe surface of the insulation layer 34 (FIG. 1G). The deposition mask 54(FIG. 1G) includes openings (“second openings” in the claims) that alignwith the vias 44 (FIG. 1G), and other elongated openings (“thirdopenings” in the claims), which determine the pattern of theredistribution conductors 12 (FIG. 2C), and the terminal contact pads 52(FIG. 2C). However, prior to forming the deposition mask 54 (FIG. 1G), acopper seed layer can be formed in the vias 44 (FIG. 1G), and on thesurface of the insulation layer 34 (FIG. 1G).

Following formation of the copper seed layer, a resist layer can beformed on the copper seed layer, and photopatterned to define thedeposition mask 54 (FIG. 1G). This patterning step is termed herein asphoto alignment step 3. Next, the wafer 20 (FIG. 2A) can be dipped in anelectroless or an electrolytic copper plating solution, such that copperis applied to areas of the seed layer not covered by the deposition mask54 (FIG. 1G). The copper can be electrolessly plated to form theconductive layer 50 (FIG. 1G) with a thickness of from about 1 μm to 10μm. In addition, the electrolessly plated copper can be plated withanother metal such as nickel, using another plating solution, such thatthe conductive layer 50 (FIG. 1G) comprises a bi-metal stack of Cu/Ni.

Next, as shown in FIG. 1H, following electroless copper plating, andnickel plating, the deposition mask 54 (FIG. 1G) can be stripped usingplasma etching or other suitable process. In addition, the exposedcopper seed layer can be removed by etching, such that just theconductive layer 50 (FIG. 1G) remains in the pattern which forms thethrough interconnects 11 (FIG. 1H), and defines the redistributionconductors 12 (FIG. 2C) and the terminal contact pads 52 (FIG. 1H).During the seed layer removal process, the nickel layer provides an etchmask for protecting the conductive layer 50. The outlined process forforming the conductive layer 50 (FIG. 1H) by electroless plating ismerely exemplary, and other processes known in the art can be employedto form the conductive layer 50 (FIG. 1H) using other metals, such asAl, Cr, Ti, Ni, W, Au, Ag, Ta, Mb. Other suitable deposition processesinclude CVD, PECVD, PVD, sputtering and evaporation.

Next, as shown in FIG. 1I, an outer insulation layer 58 (FIG. 1I) can beformed on the insulation layer 34 (FIG. 1I) and in the vias 44 (FIG.1I). The outer insulation layer 58 (FIG. 1I) covers the conductive layer50 (FIG. 1G) in the vias 44 (FIG. 1I) and the redistribution conductors12 (FIG. 2C). However, the outer insulation layer 58 (FIG. 1I) can bepatterned with openings such that the terminal contact pads 52 (FIG. 1I)remain exposed. The outer insulation layer 58 (FIG. 1I) can comprise alow dielectric constant (low k) polymer such as polyimide,polybenzoxazole (PBO), or benzocyclobutene (BCB). By way of example, theouter insulation layer 58 (FIG. 1I) can be initially blanket depositedto a desired thickness using a suitable deposition process such as spinon, positive displacement through a nozzle, screen printing orstenciling. The outer insulation layer 58 (FIG. 1I) can then bepatterned and cured using a suitable process, such as wet chemicaletching through a photo mask. Alternately, the outer insulation layer 58(FIG. 1I) can comprise a photoimageable material, such as a resist or aphotoimageable polyimide, that can be patterned directly without a photomask.

As also shown in FIG. 1I, the terminal contacts 56 (FIG. 1I), or outerlead bonds (OLB), can be formed on the terminal contact pads 52 (FIG.1I). In addition, the terminal contacts 56 (FIG. 1I) are in electricalcommunication with the through interconnects 11 (FIG. 1I), which formthe inner lead bonds (ILB). However, prior to forming the terminalcontacts 56 (FIG. 1I), under bump metallization layers can be formed onthe terminal contact pads 52 (FIG. 1I). The terminal contacts 56 (FIG.1I) can comprise metal, or solder, balls, bumps or pins, formed on theterminal contact pads using a metallization process, a stud bumpingprocess or a ball bonding process. A representative range for thediameter of the terminal contacts 56 (FIG. 1I) can be from 60-500 μm. Inaddition, the terminal contact pads 52 (FIG. 1I) and the terminalcontacts 56 (FIG. 1I), can be formed in an area array, such as a ballgrid array, a pin grid array, an edge array or a center array.

Following formation of the terminal contacts 56 (FIG. 1I), a singulatingstep can be performed to singulate the thinned semiconductor substrates14T (FIG. 1I) from the semiconductor wafer 20 (FIG. 2A). The singulatingstep can be performed using a dicing saw configured to dicesemiconductor wafers into individual dice. Alternately, rather than bysawing, the singulating step can be performed using another singulationmethod, such as cutting with a laser or a water jet, or by etching witha suitable wet or dry etchant. Prior to the singulating step, thetemporary carrier 28 (FIG. 1I), if used, can be detached from the wafer20 (FIG. 2A). Alternately, the temporary carrier 28 (FIG. 1I) can beconfigured to form the transparent covers 28S (FIG. 3B), in which caseit can be singulated with the wafer 20 (FIG. 2A) to form the transparentcovers 28S (FIG. 3B).

Referring to FIGS. 3A-3C, the semiconductor component 10 is shown. Thesemiconductor component 10 includes the thinned semiconductor substrate14T (FIG. 3B) having the pixel array 16 (FIG. 3A) and the integratedcircuits 18 (FIG. 1A). The semiconductor component 10 also includes thetransparent cover 28S (FIG. 3B) and the spacers 32 (FIG. 3B), whichattach and space the transparent cover 28S (FIG. 3B) on the thinnedsemiconductor substrate 14T (FIG. 3B). For simplicity, the transparentcover 28S (FIG. 3B) is illustrated as being formed from the temporarycarrier 28 (FIG. 1I). However, it is to be understood that thetransparent cover 28S (FIG. 3B) can comprise a separately attachedelement. In addition, the semiconductor component 10 can also includeone or more lenses (not shown) either in place of or attached to thetransparent cover 28S (FIG. 3B).

The semiconductor component 10 also includes the through interconnects11 (FIG. 3B) in the thinned semiconductor substrate 14T (FIG. 3B), whichelectrically connect the substrate contacts 26 (FIG. 3B) to the terminalcontacts 56 (FIG. 3B). Each through interconnect 11 (FIG. 3B) includesan insulated via 44 (FIG. 3B), and a portion of the conductive layer 50(FIG. 3B) lining the sidewalls of the via 44 (FIG. 3B) and the innersurface 46 (FIG. 1F) of an associated substrate contact 26 (FIG. 3B).Each through interconnect 11 (FIG. 3B) also includes portions of theouter insulation layer 58 (FIG. 3B) in the via 44 (FIG. 3B). The outerinsulation layer 58 (FIG. 3B) thus serves the dual purpose of insulatingthe back side of the component 10, and the through interconnects 11(FIG. 3B) as well.

As shown in FIG. 3C, the semiconductor component 10 also includes theredistribution conductors 12 (FIG. 3C), the terminal contact pads 52(FIG. 3C), and the terminal contacts 56 (FIG. 3C), in electricalcommunication with the through interconnects 11 (FIG. 3B). Theredistribution conductors 12 (FIG. 3C) are formed from the conductivelayer 50 (FIG. 3B), which also forms the through interconnects 11 (FIG.3B). In addition, the redistribution conductors 12 (FIG. 3C)redistribute the pattern of the substrate contacts 26 (FIG. 3B) to thepattern of the terminal contact pads 52 (FIG. 3C), and the terminalcontacts 56 (FIG. 3C). In the claims the pattern of the substratecontacts 26 (FIG. 3B) is termed the “first pattern”, and the pattern ofthe terminal contact pads 52 (FIG. 3C) and the terminal contacts 56(FIG. 3C) is termed the “second pattern”.

The semiconductor component 10 (FIGS. 3A-3C) can be used as a standalone device, and in combination with other semiconductor components tofabricate semiconductor systems for consumer products (e.g., cellphones, camcorders) and computers. As shown in FIG. 4, a semiconductorsystem 60 (FIG. 4) can include a supporting substrate 62 (FIG. 4), suchas a module substrate, a printed circuit board, or a computer motherboard wherein the semiconductor component 10 is mounted.

While a number of exemplary aspects and embodiments have been discussedabove, those of skill in the art will recognize certain modifications,permutations, additions and subcombinations thereof. It is thereforeintended that the following appended claims and claims hereafterintroduced are interpreted to include all such modifications,permutations, additions and sub-combinations as are within their truespirit and scope.

1. A method for fabricating a semiconductor component comprising: providing a semiconductor substrate comprising a substrate contact; forming a through interconnect in the substrate in electrical contact with the substrate contact; and forming a conductor on the semiconductor substrate in electrical contact with the through interconnect; wherein the forming the through interconnect step and the forming the conductor step comprise a same metal deposition step.
 2. The method of claim 1 wherein the through interconnect and the conductor comprise a same metal layer.
 3. The method of claim 1 wherein the through interconnect comprises a via from the substrate contact to the back side and a metal layer in the via in electrical contact with the substrate contact, and the conductor comprises a portion of the metal layer on a back side of the semiconductor substrate.
 4. The method of claim 1 wherein the forming the through interconnect step comprises electroless deposition of a metal layer through openings in an insulation layer on the semiconductor substrate, and the forming the conductor step comprises electroless deposition of the metal layer onto the insulation layer.
 5. A method for fabricating a semiconductor component comprising: providing a semiconductor substrate comprising a substrate contact and a surface; forming a via in the semiconductor substrate aligned with the substrate contact; forming a conductive layer in the via in electrical contact with the substrate contact; forming the conductive layer in the via into a through interconnect; and forming the conductive layer on the surface into a conductor.
 6. The method of claim 5 further comprising forming a terminal contact on the surface in electrical communication with the conductor.
 7. The method of claim 5 further comprising forming an insulation layer on the surface and in the via configured to electrically insulate the conductive layer.
 8. The method of claim 5 wherein the via and the surface are generally perpendicular to one another.
 9. The method of claim 5 wherein the substrate contact is on a circuit side of the semiconductor substrate and the surface comprises a back side of the semiconductor substrate.
 10. A method for fabricating a semiconductor component comprising: providing a semiconductor substrate comprising a circuit side, a back side, a plurality of integrated circuits on the circuit side, and a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits; forming a plurality of vias from the back side of the semiconductor substrate to the substrate contacts; forming a conductive layer in the vias and on the back side of the semiconductor substrate in electrical contact with the substrate contacts; and forming the conductive layer on the back side of the semiconductor substrate into a plurality of conductors in electrical communication with the substrate contacts.
 11. The method of claim 10 further comprising forming an insulation layer on the back side of the semiconductor substrate and in the vias.
 12. The method of claim 10 further comprising forming insulation layers in the vias prior to the forming the conductive layer step.
 13. The method of claim 10 further comprising forming a plurality of terminal contact pads on the back side in electrical communication with the conductors, and forming terminal contacts on the terminal contact pads.
 14. The method of claim 10 wherein the forming the conductive layer step comprises electroless deposition.
 15. The method of claim 10 wherein the forming the plurality of vias step comprises etching.
 16. The method of claim 10 further comprising attaching a carrier to the semiconductor substrate prior to the forming the conductive layer step.
 17. The method of claim 10 wherein each via includes a sidewall and the conductive layer lines the sidewall but leaves the via open.
 18. The method of claim 10 wherein the substrate contacts include inner surfaces and the conductive layer lines the inner surfaces.
 19. The method of claim 10 wherein the semiconductor substrate is provided on a semiconductor wafer and the method is performed on the wafer.
 20. The method of claim 10 wherein the semiconductor substrate comprises a known good die (KGD).
 21. The method of claim 10 wherein the vias are generally perpendicular to the back side and to the conductors.
 22. The method of claim 10 wherein the semiconductor substrate comprises an imager die.
 23. The method of claim 10 wherein the semiconductor substrate comprises a high speed digital logic device selected from the group consisting of a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a MEMS type device, and a solar cell.
 24. The method of claim 10 wherein the integrated circuits include radiation sensitive integrated circuits, and further comprising attaching a transparent carrier to the semiconductor substrate configured to protect the radiation sensitive integrated circuits during the forming step.
 25. A method for fabricating a semiconductor component comprising: providing a semiconductor substrate comprising a circuit side, a back side, a plurality of integrated circuits on the circuit side, and a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits; forming a plurality of vias from the back side of the semiconductor substrate to the substrate contacts; forming a conductive layer in the vias and on the back side of the semiconductor substrate, the conductive layer at least partially lining the vias and the substrate contacts; forming the conductive layer on the back side of the semiconductor substrate into a plurality of conductors in electrical communication with the substrate contacts; and forming an insulation layer on the back side and in the vias at least partially covering the conductive layer.
 26. The method of claim 25 wherein the substrate is contained on a semiconductor wafer and the method is performed on the wafer.
 27. The method of claim 25 wherein the forming the conductive layer step comprises electrolessly depositing a seed layer in the vias and on the back side, forming a deposition mask on the back side, depositing a copper layer through the deposition mask onto the seed layer, and removing the deposition mask.
 28. The method of claim 25 wherein the conductors include terminal contact pads, and further comprising forming terminal contacts on the terminal contact pads.
 29. The method of claim 25 wherein the conductive layer comprises an electrolessly plated copper/nickel stack.
 30. The method of claim 25 wherein the forming the vias step comprises etching the semiconductor substrate through an etch mask on the back side having openings aligned with the substrate contacts.
 31. The method of claim 25 wherein the forming the vias step comprises etching the semiconductor substrate through an insulation layer on the back side having openings aligned with the substrate contacts.
 32. The method of claim 25 further comprising forming insulation layers in the vias prior to the forming the conductive layer step.
 33. The method of claim 25 further comprising forming a transparent carrier on the semiconductor substrate configured to support the semiconductor substrate prior to the forming the conductive layer step.
 34. The method of claim 25 further comprising mounting the semiconductor substrate to a supporting substrate of a system.
 35. The method of claim 25 further comprising thinning the semiconductor substrate from the back side prior to the forming the conductive layer step.
 36. A method for fabricating a semiconductor component comprising: providing a semiconductor substrate comprising a circuit side, a back side, a plurality of integrated circuits on the circuit side, and a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits; forming a first insulation layer on the back side having a plurality of first openings aligned with the substrate contacts; etching a plurality of vias through the first openings to the substrate contacts; forming a deposition mask on back side having second openings aligned with the vias and elongated third openings; electrolessly depositing a conductive layer through the first openings and the second openings into the vias to form through interconnects, and through the third openings onto the back side to form back side conductors in electrical communication with the through interconnects; removing the deposition mask; and forming a second insulation layer on the back side covering the through interconnects and at least partially covering the conductors.
 37. The method of claim 36 wherein the etching step further comprises forming an etch mask on the first insulation layer and the etching the vias step comprises etching through the etch mask.
 38. The method of claim 36 wherein the substrate contacts comprise bond pads or redistribution pads.
 39. The method of claim 36 wherein the conductors include terminal contact pads, and further comprising forming terminal contacts on the terminal contact pads.
 40. The method of claim 36 wherein the first insulation layer comprises a polymer or a photoimageable polymer.
 41. The method of claim 36 wherein the second insulation layer comprises a polymer or a photoimageable polymer.
 42. The method of claim 36 wherein the semiconductor substrate is contained on a substrate comprising a plurality of semiconductor substrates and the method is performed on the substrate.
 43. The method of claim 36 wherein the substrate contacts are in a first pattern and the conductors include terminal contact pads in a second pattern.
 44. The method of claim 36 wherein the conductors include terminal contact pads in an area array, and further comprising forming terminal contacts on the terminal contact pads.
 45. The method of claim 36 further comprising thinning the semiconductor substrate from the back side prior to the forming the first insulation layer step.
 46. The method of claim 36 wherein the semiconductor substrate is contained on a semiconductor wafer, and further comprising attaching the wafer to a transparent carrier, thinning the wafer using the carrier, and then singulating the wafer and the carrier.
 47. The method of claim 36 further comprising mounting the component to a supporting substrate of a semiconductor system.
 48. The method of claim 36 wherein the semiconductor substrate includes a passivation layer, and the etching the vias step comprises etching the vias to the passivation layer, and then etching the passivation layer in the vias from the substrate contacts.
 49. The method of claim 36 wherein the conductive layer has a thickness of from 1 μm to 10 μm.
 50. The method of claim 36 wherein the conductive layer comprises copper.
 51. The method of claim 36 further comprising forming an insulation layer in each via prior to the forming the conductive layer step.
 52. A semiconductor component comprising: a semiconductor substrate comprising a plurality of integrated circuits; a plurality of substrate contacts on the semiconductor substrate in electrical communication with the integrated circuits; a plurality of through interconnects in the semiconductor substrate in electrical contact with the substrate contacts; a plurality of conductors on a surface of the semiconductor substrate in electrical contact with the through interconnects; the through interconnects and the conductors comprising a same conductive layer.
 53. The semiconductor component of claim 52 wherein the surface comprises a back side of the semiconductor substrate and the through interconnects are generally perpendicular to the surface.
 54. The semiconductor component of claim 52 wherein the through interconnects comprise insulated vias extending from the substrate contacts to the surface, and the conductive layer lines the vias and extends over the surface.
 55. The semiconductor component of claim 52 wherein the substrate contacts are located on a circuit side of the semiconductor substrate, and the surface comprises a back side of the semiconductor substrate.
 56. A semiconductor component comprising: a semiconductor substrate comprising a plurality of integrated circuits; a plurality of substrate contacts on the semiconductor substrate in electrical communication with the integrated circuits; a plurality of vias extending through the semiconductor substrate to the substrate contacts; a conductive layer in the vias and on the semiconductor substrate in physical and electrical contact with the substrate contacts; and a plurality of conductors on the semiconductor substrate comprising portions of the conductive layer.
 57. The semiconductor component of claim 56 further comprising an insulation layer on the semiconductor substrate and in the vias.
 58. The semiconductor component of claim 56 further comprising an insulation layer in each via.
 59. The semiconductor component of claim 56 further comprising a plurality of terminal contact pads on the conductors, and terminal contacts on the terminal contact pads.
 60. The semiconductor component of claim 56 wherein each via includes a sidewall and the conductive layer lines the sidewall but leaves the via open.
 61. The semiconductor component of claim 56 wherein the substrate contacts include inner surfaces and the conductive layer lines the inner surfaces.
 62. The semiconductor component of claim 56 wherein the semiconductor substrate comprises a known good die (KGD).
 63. A semiconductor component comprising: a semiconductor substrate comprising a circuit side, a back side, a plurality of integrated circuits on the circuit side, and a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits; a plurality of vias in the semiconductor substrate extending from the back side of the semiconductor substrate to the substrate contacts; a conductive layer on the back side of the semiconductor substrate at least partially lining the vias and the substrate contacts; a plurality of conductors comprising portions of the conductive layer in electrical communication with the substrate contacts; and an insulation layer on the back side and in the vias at least partially covering the conductive layer.
 64. The semiconductor component of claim 63 wherein the conductors include terminal contact pads in an area array, and further comprising a plurality of terminal contacts on the terminal contact pads.
 65. The semiconductor component of claim 63 wherein the semiconductor substrate comprises an imager die.
 66. The semiconductor component of claim 63 wherein the semiconductor substrate comprises a high speed digital logic device selected from the group consisting of a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a MEMS type device, and a solar cell.
 67. The semiconductor component of claim 63 wherein the integrated circuits include radiation sensitive integrated circuits, and further comprising a transparent cover attached to the semiconductor substrate configured to protect the radiation sensitive integrated circuits.
 68. The semiconductor component of claim 63 wherein the conductive layer has a thickness of from 1 μm to 10 μm.
 69. The semiconductor component of claim 63 wherein the conductive layer comprises copper.
 70. The semiconductor component of claim 63 wherein the conductive layer comprises a copper-nickel stack.
 71. The semiconductor component of claim 63 wherein the substrate contacts are in a first pattern, and the conductors include terminal contact pads in a second pattern.
 72. The semiconductor component of claim 63 wherein the conductors include terminal contact pads in an area array, and further comprising terminal contacts on the terminal contact pads.
 73. The semiconductor component of claim 63 wherein the substrate contacts comprise bond pads or redistribution pads.
 74. The semiconductor component of claim 63 wherein the semiconductor substrate has a thickness of from 10 μm to 700 μm.
 75. A semiconductor component comprising: a semiconductor substrate having a circuit side, a back side and a plurality of integrated circuits; a plurality of substrate contacts on the circuit side in electrical communication with the integrated circuits having inner surfaces; a plurality of through interconnects in the semiconductor substrate comprising electrically insulated vias aligned with the substrate contacts, and a conductive layer at least partially lining the vias and the inner surfaces of the substrate contacts; and a plurality of conductors on the back side comprising portions of the conductive layer.
 76. The semiconductor component of claim 75 further comprising an outer insulating layer at least partially covering the back side and the through interconnects.
 77. The semiconductor component of claim 75 wherein the conductors include terminal contact pads in an area array, and the component includes terminal contacts on the terminal contact pads.
 78. The semiconductor component of claim 75 wherein the semiconductor substrate comprises a thinned, tested semiconductor die.
 79. The semiconductor component of claim 75 wherein the semiconductor substrate comprises an imager die, and further comprising a transparent cover on the imager die.
 80. The semiconductor component of claim 75 wherein the conductors comprise redistribution conductors configured to redistribute a pattern of the substrate contacts.
 81. The semiconductor component of claim 75 further comprising a supporting substrate of a system and wherein the semiconductor component is mounted to the supporting substrate.
 82. The semiconductor component of claim 75 wherein the conductive layer includes portions on the back side circumjacent to the vias.
 83. A system comprising: a supporting substrate; and at least one semiconductor substrate on the supporting substrate comprising a plurality of integrated circuits, a plurality of substrate contacts in electrical communication with the integrated circuits, and a plurality of through interconnects and redistribution conductors; each through interconnect comprising a via aligned with a substrate contact and a conductive layer at least partially lining the via in physical and electrical contact with the substrate contact, each conductor comprising a portion of the conductive layer.
 84. The system of claim 83 wherein the conductors include terminal contact pads in an area array, and further comprising a plurality of terminal contacts on the terminal contact pads.
 85. The system of claim 83 wherein the semiconductor substrate comprises an imager die.
 86. The system of claim 83 wherein the semiconductor substrate comprises a high speed digital logic device selected from the group consisting of a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a MEMS type device, and a solar cell.
 87. The system of claim 83 wherein the integrated circuits include radiation sensitive integrated circuits, and further comprising a transparent cover attached to the semiconductor substrate configured to protect the radiation sensitive integrated circuits.
 88. The system of claim 83 wherein the supporting substrate comprises a module substrate, a circuit board or a computer mother board.
 89. A system comprising: a supporting substrate; and a component on the supporting substrate comprising a plurality of substrate contacts, a plurality of through interconnects in electrical contact with the substrate contacts, a plurality of back side conductors in electrical communication with the through interconnects, and a plurality of terminal contacts in electrical communication with the conductors flip chip mounted to the supporting substrate; the through interconnects and the conductors comprising a same conductive layer.
 90. The system of claim 89 wherein the terminal contacts comprise the same conductive layer.
 91. The system of claim 89 wherein each through interconnect comprises a via, and a metal layer in the via in electrical contact with a substrate contact, and the conductors comprise portions of the metal layer.
 92. The system of claim 89 wherein the supporting substrate comprises a module substrate, a circuit board or a computer mother board.
 93. The system of claim 89 wherein the component comprises a semiconductor die comprising a plurality of integrated circuits in electrical communication with the substrate contacts, and the conductive layer at least partially lines the substrate contacts. 